package Generic_Expressions is

   generic
   with function "+" (X : Item) return Item is <>;
   with function "-" (X : Item) return Item is <>;
   with function "+" (X, Y : Item) return Item is <>;
   with function "-" (X, Y : Item) return Item is <>;
   with function "*" (X, Y : Item) return Item is <>;
   with function "/" (X, Y : Item) return Item is <>;

   type Generic_Expression is

end Generic_Expressions;
